Figure 2.

The variability due to tissue-specific differences in cytosine methylation greatly exceeds all other sources of variability. We show the mean and range of correlation coefficients for all of the experimental replicates (three independent HELP assays performed on DNA from a single mouse) and biological replicates (three different mice) for the HpaII/MspI ratios. An illustrative scattergram is shown for each situation. The variability involving HpaII/MspI representations across tissues greatly exceeds any of the other sources of variability in the experimental system.